* Berdych registers 450th career match win
* Reaches semis without having dropped a set
* Nadal a three-time runner-up in Miami (Adds quotes)
MIAMI, March 27 (Reuters) - World number one Rafa Nadal took another step towards a first Miami title by out-slugging big-hitting Canadian Milos Raonic 4-6 6-2 6-4 on Thursday to reach the semi-finals of the Sony Open.
Nadal, a three-time runner-up on the Miami hardcourts, will play seventh seed Tomas Berdych for a place in Sunday's final after the Czech eased into the last four with 6-4 7-6 (3) win over Ukraine's Alexandr Dolgopolov.
The other semi-final will see world number two Novak Djokovic take on Japan's Kei Nishikori, who has already beaten fourth seed David Ferrer and 17-time grand slam winner Roger Federer.
Nadal's resume includes 62 career titles, including two this year but the Miami trophy has consistently eluded the 13-time grand slam winner.
The Spaniard, however, has been in brilliant form in Miami appearing determined to correct that oversight.
"It's a very important victory for me," said Nadal. "Very hard to play against these kind of players and especially when the match didn't start the way that you would like.
"When you start losing opportunities, you feel that you are going to be in trouble, because one game he going to play aggressive and you will be in his hands, and the next thing is that game arrived,
"I was lucky at the beginning of the second set I started with a break and was very important for me.
"I felt that I finished the match playing better."
Raonic's booming serve, that included a couple at 140-mph plus, kept Nadal on his heels in the opening set but it was the world number one's own serve that let him down when he double faulted on break point at 5-4 down to gift the 12th seeded Canadian the set.
It marked the first time Nadal's serve had been broken in Miami and the unhappy Spaniard struck back by breaking Raonic twice to surge to a 4-0 lead in the second on the way to leveling the match.
He then gained the upper hand in the third set with a decisive break at 4-3 then held serve to complete the victory.
"So close isn't good enough," said Raonic, who will move back into the top 10 when the new rankings come out on Monday. "There is a lot of things I could say about 'almost' in my life.
"But there is a lot of things, just how to deal with the situation, what the importance for my focus are throughout these matches, especially matches like this where you've just got to hope to get things right.
"I'm very proud with how I dealt with the conditions and I'm just not necessarily the most ecstatic about the result."
Earlier, Berdych quietly worked his way into the last four without dropping a set.
The match was briefly halted by rain with the score tied 4-4 in the opening set, but when the players returned to an overcast centre court Berdych took control, holding serve and breaking the 22nd seed to grab the 1-0 lead.
Dolgopolov hit back with an early break in the second on way to a 5-3 lead but Berdych broke the Ukrainian at 5-5 to help force a tiebreak which he easily won to register his 450th career match win.
"I was a break down since the beginning of the first set. Then break down in the second set, so it didn't look that well," said Berdych.
"But I managed, especially end of the second set, I hold pretty well and that's what I'm very pleased with." (Editing by Frank Pingue/Greg Stutchbury)